Convertible tops for autos typically comprise a foldable frame including a pair of unitary or sectional parallel side rails extending alongside and above the passenger compartment with bows extending laterally between the side rails, over which is stretched a fabric covering. The frame typically folds together into a generally U-shaped collapsed configuration for storage. The U-shape is formed by the side rails pivoted down to lie to the rear, connected by the bows extending between the rear most ends of the side rails and any supporting pillar members.
When the mechanism is power operated, one or more power cylinders are drivingly connected to drive members extending to the rear of each side rail so that they will pull each side rail to the rear to "accordion" fold the pivoted-together sections of the side rails when the top is lowered.
In this design the top frame when folded down is of a considerable depth which in turn produces an undesirable, relatively bulky, contour behind the rear seat.
Auto styling in recent years has featured inwardly sloping side glass so that the roof line is narrower than the passenger compartment. When this styling is repeated in the convertible models, a reduction of rear seat width usually results since the side rails are necessarily spaced closer together than the normal width of the rear seats. When the top is lowered, the side rails are moved into storage spaces located to reduce the width of the rear seat.
In U.S. Pat. No. 4,573,732, issued to the present inventor, there is disclosed a manually operated convertible top frame featuring unitary side rails each pivoted to a rear pillar, which side rails swing out to diverge forwardly when being pivoted down to enable the forward ends to be positioned further outward than the raised position spacing of the side rails, to avoid the loss of rear seat width.
The present invention is concerned with achieving a similar result in power operated tops with side rails composed of pivoted together sections.
The present inventor has previously developed such a top frame for body styles having quarter windows to the rear of the side door windows. In such previous designs, the top frame included a "B" pillar member on each side located just forward of the respective quarter window which was hinged thereto, with a "C" pillar extending along the rear edge of the quarter window.
Each "B" and "C" pillar formed a part of the frame folding linkage system which enabled stable control over leading ends of the folded sectional side rails, with forward located power cylinders providing a compact collapsed height. A diverging angle of the side rail sections preserved the rear seat width.
This design carried the quarter windows down into the side wells as the frame was lowered. The laterally curved contour of the quarter windows creates a substantial width of the quarter window, which in turn required the pivot point of the "B" pillar to be located sufficiently rearward so that storage of the glass itself did not require a reduction in rear seat width. One of the window edges was hinged to the "B" pillar, also necessitating a pivot location relatively far spaced to the rear. This location of the pivot axis resulted in the quarter windows moving down into the region occupied by the rear wheel wells, necessitating controlled hinging of the quarter windows to clear these structures.
The aforementioned prior design also incorporated complex linkages to accommodate the swing out action of the side rails to the straight back pivoting of the "B" pillars as the frame is lowered.
In U.S. Pat. No. 2,267,471, issued to Keller, there is disclosed a convertible top frame in which the quarter windows are carried by the convertible frame so as to be lowered as the frame is lowered. Such top frame does not provide a solution to the problem of reduced width rear seats, as outlined above. The quarter window frame in that design does not form a part of the frame linkage, and adds to the complexity of the top frame.